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  #18  
Old September 27th 05, 03:44 AM
CTR
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Nick,

Lets keep to the facts and lighten up on the name calling.

1) On slide 4 of your presentation you state the CH-53 max payload as
36,515 LBS. From slide 5 you show the max ferry range to be
approximately 1,100 KM. In the Sikorsky data you referenced however,
to achieve both these points the CH-53 has to be reconfigured by adding
or removing external and internal aux fuel tanks. The external tanks
by your own statement weigh 1,600 LBS. I extrapolated from the
Sikorsky curve the internal aux tanks to weigh approx 1,500 LBS (please
supply a wt. if you disagree). The V-22 does not require aux tanks to
meet this range. Therefore to be an unbiased comparison you need to
subtract the weight of the aux tanks from the max payload value. .Or
conversely not use the range provided by these aux tanks

2) From the Sikorsky data, any mission requiring air refueling reduces
the CH-53 range by 6,000 LBS. From this same chart I assumed that was
due to the combined weight of aux tanks and refuel hardware. You
stated that this in a inflight performance restriction. Either way,
does not this large drop in payload deserve at least a foot note on
slide 4 and 5. Especially since the V-22 does not suffer from this
restriction?

3) To make your case you are willing to use the best performance data
for the CH-53 with or without added aux tanks and not bothering to note
the air refuel drop in payload. However when asked to consider the
increase in V-22 maximum gross to 60,500 pounds (STOL) from the
52,600pounds (V/STOL) you dismissed this as being unrealistic. Data
source Naval Helicopter Association.

4) When you admitted to an error by omitting the CH-53 externat aux
tank weight, you said your case was still sound because you also made
an error on the V-22 data. Maybe in PPRUNE two wrongs make a right.
But in a professional technical paper two wrongs just call into
question all data that is presented. If you data is wrong (even if it
is minor), admit the mistake, correct it and check the rest of your
data for other errors.

Finally, if you plan to just post this presentation on the web to have
online bull sessions, your presentation and attitude is great
entertainment. But if you plan to submit this as a paper or
presentation to a professional society, don't bias the facts and loose
the attitude dude.

Have fun,

CTR

PS I have 25 years of Aerospace engineering experience on many verticle
lift aircraft including the AV-8B Harrier, won multiple awards for
best paper by both AHS and SAE and have seven patents in the field of
aerospace technology. How about you?